The present invention relates to electrical switches and, in particular, to solenoid switches for use in internal combustion engine ignition systems for vehicles, lawn and garden equipment, and the like.
Solenoid switches are conventionally used with internal combustion engines to close the circuit between a battery and the starter motor during ignition. A typical solenoid switch includes an electrical coil in which a metal core is slidably received. The metal core acts as an actuator to shift a contact bridge when the coil is energized. The shifting of the metal core interconnects the contact bridge with two electrical contacts, one contact having a principal or major lead connected to the battery and the other contact having the other principal or major lead connected to the starter motor. Electrical power is supplied to the coil through separate smaller electrical leads which are connected to the battery and ignition switch.
In most solenoids, due to the orientation of the electrical contacts relative to the sliding core, the battery and starter motor leads extend to the side, i.e., perpendicular to the direction of travel of the core. This orientation is inconvenient, since it results in the solenoid switch assembly having electrical leads that extend at various angles from the side of the assembly housing. The solenoid assembly therefor cannot be easily mounted in confined spaces nor linearly between the battery and starter motor, since the solenoid assembly is uncentered or positioned off to one side of the electrical leads. The solenoid assembly must, therefore, be stationarily mounted in order to prevent the assembly from moving or flopping about. The variously extending leads make it especially difficult to mount the solenoid assembly in confined areas since all of the leads must be accessible.
Another difficulty associated with conventional solenoids is that the switch is made up of relatively small elements that require time consuming assembly. The various elements must each be individually secured within the solenoid containment housing by some type of fastener. This increases the cost of manufacturing and assembling these devices.
In addition, prior known solenoids have been relatively expensive to repair or replace. Further, the necessity for sustained reliability over long periods and in varying climatic conditions has previously kept the cost of conventional solenoids at a relatively high level.